Adjuntas Municipio area

Adjuntas Municipio, Puerto Rico covers 67 square miles: 66.6 square miles of land and 0.401 square miles of water. Its county seat is Adjuntas. An estimated 17,994 people lived there in 2025.

Official Census measurements · GEOID 720012026 Gazetteer · retrieved September 27, 2026
Land area66.6 mi²
Water area0.401 mi²
Population (2025)17,994
People per mi²270

County outline

Generalized outline of Adjuntas Municipio, Puerto Rico
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Adjuntas Municipio is located

Adjuntas Municipio highlighted on a map of all U.S. county equivalents. Puerto Rico is repositioned as an inset at the common scale. About the maps

Area breakdown

Land accounts for 99.4% of Adjuntas Municipio’s measured area and water for 0.6%. Its combined area converts to 173.6 square kilometers or approximately 42,899 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land66.628172.56642,641.9
Water0.4011.039256.6
Total67.029173.60442,898.6

How Adjuntas Municipio compares

By original Census land area, Adjuntas Municipio ranks #10 of 78 in Puerto Rico and #3107 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.587 times the Puerto Rico county-equivalent median of 42 square miles. It accounts for 1.9% of the combined county land area in the state.

See the complete Puerto Rico ranking · What counts as a county equivalent?

Population and density of Adjuntas Municipio

The Census Bureau estimates that 17,994 people lived in Adjuntas Municipio on July 1, 2025. That ranks #2,001 of 3,222 county equivalents nationally and #62 of 78 in Puerto Rico. Since the April 1, 2020 estimates base of 18,018, the population has declined by 24 (−0.1%), compared with −3.1% for Puerto Rico as a whole.

With 66.6 square miles of land, that is 270 people per square mile (104 per km²), placing Adjuntas Municipio #547 nationally for density and #72 in Puerto Rico. The median county equivalent has 47 people per square mile; the Puerto Rico median is 754. Put another way, there are about 2.4 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate18,00818,01217,89217,87917,98217,994
Change—+4−120−13+103+12

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Adjuntas Municipio

Puerto Rico has no incorporated places below the municipio: Adjuntas Municipio is itself the local government. The Census Bureau describes the settlements inside it, such as zonas urbanas and comunidades, as statistical places, and publishes no separate annual estimates for them.

Metropolitan area

Adjuntas Municipio is not part of any metropolitan or micropolitan statistical area in the Office of Management and Budget’s July 2023 delineation; 1,306 other county equivalents are also outside one. These areas are built around an urban core of at least 10,000 people plus the counties tied to it by commuting, so counties outside them are generally rural.

ZIP codes

4 ZIP Code Tabulation Areas have land in Adjuntas Municipio; 2 of them have most of their land inside the county, and the others mainly cover neighboring areas.

00601006310064100731

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Adjuntas Municipio

Adjuntas Municipio shares a land border with 6 county equivalents. It has more land than 3 of them. The largest neighbor is Ponce Municipio (114.9 mi²) and the smallest is Guayanilla Municipio (42.2 mi²). Together with its neighbors, Adjuntas Municipio forms a block of 511.3 mi² of land, of which it holds 13%.

Map of Adjuntas Municipio and the 6 county equivalents that border it Utuado Municipio, Puerto Rico: 113.6 mi² landPeñuelas Municipio, Puerto Rico: 44.7 mi² landLares Municipio, Puerto Rico: 61.4 mi² landYauco Municipio, Puerto Rico: 67.8 mi² landPonce Municipio, Puerto Rico: 114.9 mi² landGuayanilla Municipio, Puerto Rico: 42.2 mi² land
Adjuntas Municipio (dark) and its bordering county equivalents. Select a neighbor to open its profile. Drawn from the 2025 Census cartographic boundaries in an equal-area projection. How borders are determined.
Bordering county equivalentLand mi²Size vs. AdjuntasCompare
Ponce Municipio114.91.7× largerCompare
Utuado Municipio113.61.7× largerCompare
Yauco Municipio67.8about the sameCompare
Lares Municipio61.41.1× smallerCompare
Peñuelas Municipio44.71.5× smallerCompare
Guayanilla Municipio42.21.6× smallerCompare

How big is Adjuntas Municipio compared with U.S. states?

Adjuntas Municipio has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 16 times as much. Puerto Rico’s county land could hold about 51 areas the size of Adjuntas Municipio.

Land area: Adjuntas Municipio and the closest-sized states
Adjuntas Municipio66.6 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 8.16 miles (13.1 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Adjuntas Municipio?

Adjuntas Municipio has more land than 115 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Adjuntas Municipio66.6 mi²
Puerto Rico median42 mi²
National median604.5 mi²

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Adjuntas Municipio at #3,135 nationally by total area, 28 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 0.6%, compared with a national county-equivalent median of 1.2% — 0.6 percentage points lower. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Adjuntas Municipio in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#3106Yauco Municipio, Puerto Rico67.8Compare
#3107Adjuntas Municipio, Puerto Rico66.6This county
#3108Ciales Municipio, Puerto Rico66.6Compare

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.

Representative coordinates

The Census internal point is 18.181590, -66.758202. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 172,564,617 m²; AWATER: 1,038,968 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How big is Adjuntas Municipio?

Adjuntas Municipio, Puerto Rico has 66.6 square miles (172.6 km²) of land and 0.401 square miles of water, for a total area of 67 square miles. It ranks #3107 of 3,222 U.S. county equivalents by land area.

Is Adjuntas Municipio the largest county in Puerto Rico?

No. Adjuntas Municipio ranks #10 of 78 in Puerto Rico by land area. The largest is Arecibo Municipio, with 126 square miles of land.

What counties border Adjuntas Municipio?

Adjuntas Municipio shares a land border with Utuado Municipio, Peñuelas Municipio, Lares Municipio, Yauco Municipio, Ponce Municipio, and Guayanilla Municipio.

What is the population of Adjuntas Municipio?

The Census Bureau estimates Adjuntas Municipio had 17,994 residents on July 1, 2025, ranking #2,001 of 3,222 county equivalents. That is 270 people per square mile of land.

What is the county seat of Adjuntas Municipio?

The county seat of Adjuntas Municipio is Adjuntas.

Is Adjuntas Municipio part of a metropolitan area?

No. Adjuntas Municipio is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.

How many ZIP codes are in Adjuntas Municipio?

4 ZIP Code Tabulation Areas have land in Adjuntas Municipio, and 2 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Adjuntas Municipio compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 15.5 times as much land.

How many acres of land are in Adjuntas Municipio?

The land measurement converts to approximately 42,642 acres. Including water, total area is approximately 42,899 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

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